A team of Australian researchers is hoping their detective work in examining DNA sequencing will help in the treatment of familial bowel cancer. They want to know more about Lynch Syndrome, and their work has been published in the journal Nature Genetics. An international database charting gene changes means families previously in the dark about their genetic risk can be offered definitive testing.

Transcript

TONY EASTLEY: A team of Australian researchers is hoping their detective work in examining DNA sequencing will help in the treatment of familial bowel cancer.

They want to know more about Lynch Syndrome, and their work has been published in the journal Nature Genetics.

An international database charting gene changes means families previously in the dark about their genetic risk can be offered definitive testing.

Rachael Brown reports.

RACHAEL BROWN: Lynch Syndrome is an inheritable form of bowel cancer that occurs usually between the ages of 20 and 40.

Researchers have long known the gene responsible for the syndrome, which can also lead to gynaecological, endometrial and ovarian cancers, but the interpretation of gene sequencing in vulnerable families has proved difficult.

Head of the Royal Melbourne Hospital's Colorectal Medicine and Genetics Department, professor Finlay Macrae, explains.

FINLAY MACRAE: The information that comes out is in three classes. In the first class, a change was found which is definitely known to disrupt the function of the gene and therefore cause cancers in the family. There's another group where they can't find a change, and that's a puzzle. But there's a third group where a change is identified in the DNA, but we're not sure whether it's damaging or not - and that turns out to be about a third of the cases.

RACHAEL BROWN: So, 45 experts in genetics and cancer are now analysing information being channelled into a global database.

FINLAY MACRAE: Well we've had breakthroughs in being able to assemble information that is otherwise in hidden corners around the world, either published or unpublished and directing them to a database that we have on the internet to enable an interpretation about the gene changes that's occurred in any one particular family that enables us to confidently say this change causes cancer across the family or it doesn't.

RACHAEL BROWN: Fifty-year-old Jenny Jenkins was diagnosed with Lynch Syndrome 17 years ago, and she's from a family with a strong history of cancers.

JENNY JENKINS: We were a very fortunate family in that we were one of the first to be able to make use of genetic testing and be provided with a definite answer about carrying this mutation.

RACHAEL BROWN: This consumer representative for the Cancer Council says the global database will now help countless families make better informed decisions.

JENNY JENKINS: Before you go off to make big decisions, you really need to be so confident with the information you're basing that on; you're deciding to go ahead with, for example, annual surveillance, having colonoscopy done every year, mammograms done every year.

You're deciding on treatment approaches like having a hysterectomy done, or ovaries removed. Removal of large bowel, or double mastectomies.

And you're also managing the information within your family, so helping your children as they get older, and approach the concept of doing their own testing. And perhaps even for young families, they may consider pre-implantation embryo genetic testing if they're confident that the information that they have is accurate.

RACHAEL BROWN: Professor Macrae says the database could have wider implications for other rare genetic diseases.

FINLAY MACRAE: We're leading the field across all 26,000 genes across the genome, in terms of a process by which we can handle this question of interpreting genetic changes. Because, you're probably aware, we're in the middle of a genetic revolution in terms of the capacity to find gene changes in your genome or my genome.

RACHAEL BROWN: He says it could help with the interpretation of genetic changes that occur in familial breast cancer, BRCA genes, and in inheritable neurological conditions and blood diseases.